calendar/lib.php

   1 <?php // $Id$
   2
   3 /////////////////////////////////////////////////////////////////////////////
   4 //                                                                         //
   5 // NOTICE OF COPYRIGHT                                                     //
   6 //                                                                         //
   7 // Moodle - Calendar extension                                             //
   8 //                                                                         //
   9 // Copyright (C) 2003-2004  Greek School Network            www.sch.gr     //
  10 //                                                                         //
  11 // Designed by:                                                            //
  12 //     Avgoustos Tsinakos (tsinakos@teikav.edu.gr)                         //
  13 //     Jon Papaioannou (pj@moodle.org)                                     //
  14 //                                                                         //
  15 // Programming and development:                                            //
  16 //     Jon Papaioannou (pj@moodle.org)                                     //
  17 //                                                                         //
  18 // For bugs, suggestions, etc contact:                                     //
  19 //     Jon Papaioannou (pj@moodle.org)                                     //
  20 //                                                                         //
  21 // The current module was developed at the University of Macedonia         //
  22 // (www.uom.gr) under the funding of the Greek School Network (www.sch.gr) //
  23 // The aim of this project is to provide additional and improved           //
  24 // functionality to the Asynchronous Distance Education service that the   //
  25 // Greek School Network deploys.                                           //
  26 //                                                                         //
  27 // This program is free software; you can redistribute it and/or modify    //
  28 // it under the terms of the GNU General Public License as published by    //
  29 // the Free Software Foundation; either version 2 of the License, or       //
  30 // (at your option) any later version.                                     //
  31 //                                                                         //
  32 // This program is distributed in the hope that it will be useful,         //
  33 // but WITHOUT ANY WARRANTY; without even the implied warranty of          //
  34 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the           //
  35 // GNU General Public License for more details:                            //
  36 //                                                                         //
  37 //          http://www.gnu.org/copyleft/gpl.html                           //
  38 //                                                                         //
  39 /////////////////////////////////////////////////////////////////////////////
  40
  41 // These are read by the administration component to provide default values
  42 define('CALENDAR_DEFAULT_UPCOMING_LOOKAHEAD', 21);
  43 define('CALENDAR_DEFAULT_UPCOMING_MAXEVENTS', 10);
  44 define('CALENDAR_DEFAULT_STARTING_WEEKDAY',   1);
  45 // This is a packed bitfield: day X is "weekend" if $field & (1 << X) is true
  46 // Default value = 65 = 64 + 1 = 2^6 + 2^0 = Saturday & Sunday
  47 define('CALENDAR_DEFAULT_WEEKEND',            65);
  48
  49 // Fetch the correct values from admin settings/lang pack
  50 // If no such settings found, use the above defaults
  51 $firstday = isset($CFG->calendar_startwday) ? $CFG->calendar_startwday : get_string('firstdayofweek');
  52 if(!is_numeric($firstday)) {
  53     define ('CALENDAR_STARTING_WEEKDAY', CALENDAR_DEFAULT_STARTING_WEEKDAY);
  54 }
  55 else {
  56     define ('CALENDAR_STARTING_WEEKDAY', intval($firstday) % 7);
  57 }
  58 define ('CALENDAR_UPCOMING_DAYS', isset($CFG->calendar_lookahead) ? intval($CFG->calendar_lookahead) : CALENDAR_DEFAULT_UPCOMING_LOOKAHEAD);
  59 define ('CALENDAR_UPCOMING_MAXEVENTS', isset($CFG->calendar_maxevents) ? intval($CFG->calendar_maxevents) : CALENDAR_DEFAULT_UPCOMING_MAXEVENTS);
  60 define ('CALENDAR_WEEKEND', isset($CFG->calendar_weekend) ? intval($CFG->calendar_weekend) : CALENDAR_DEFAULT_WEEKEND);
  61 define ('CALENDAR_URL', $CFG->wwwroot.'/calendar/');
  62 define ('CALENDAR_TF_24', '%H:%M');
  63 define ('CALENDAR_TF_12', '%I:%M %p');
  64
  65 define ('CALENDAR_MAXCOURSES', 3);
  66
  67 $CALENDARDAYS = array('sunday','monday','tuesday','wednesday','thursday','friday','saturday');
  68
  69
  70
  71 function calendar_get_mini($courses, $groups, $users, $cal_month = false, $cal_year = false) {
  72     global $CFG, $USER;
  73
  74     $display = &New stdClass;
  75     $display->minwday = get_user_preferences('calendar_startwday', CALENDAR_STARTING_WEEKDAY);
  76     $display->maxwday = $display->minwday + 6;
  77
  78     $content = '';
  79
  80     if(!empty($cal_month) && !empty($cal_year)) {
  81         $thisdate = usergetdate(time()); // Date and time the user sees at his location
  82         if($cal_month == $thisdate['mon'] && $cal_year == $thisdate['year']) {
  83             // Navigated to this month
  84             $date = $thisdate;
  85             $display->thismonth = true;
  86         }
  87         else {
  88             // Navigated to other month, let's do a nice trick and save us a lot of work...
  89             if(!checkdate($cal_month, 1, $cal_year)) {
  90                 $date = array('mday' => 1, 'mon' => $thisdate['mon'], 'year' => $thisdate['year']);
  91                 $display->thismonth = true;
  92             }
  93             else {
  94                 $date = array('mday' => 1, 'mon' => $cal_month, 'year' => $cal_year);
  95                 $display->thismonth = false;
  96             }
  97         }
  98     }
  99     else {
 100         $date = usergetdate(time()); // Date and time the user sees at his location
 101         $display->thismonth = true;
 102     }
 103
 104     // Fill in the variables we 're going to use, nice and tidy
 105     list($d, $m, $y) = array($date['mday'], $date['mon'], $date['year']); // This is what we want to display
 106     $display->maxdays = calendar_days_in_month($m, $y);
 107
 108     if (get_user_timezone_offset() < 99) {
 109         // We 'll keep these values as GMT here, and offset them when the time comes to query the db
 110         $display->tstart = gmmktime(0, 0, 0, $m, 1, $y); // This is GMT
 111         $display->tend = gmmktime(23, 59, 59, $m, $display->maxdays, $y); // GMT
 112     } else {
 113         // no timezone info specified
 114         $display->tstart = mktime(0, 0, 0, $m, 1, $y);
 115         $display->tend = mktime(23, 59, 59, $m, $display->maxdays, $y);
 116     }
 117
 118     $startwday = dayofweek(1, $m, $y);
 119
 120     // Align the starting weekday to fall in our display range
 121     // This is simple, not foolproof.
 122     if($startwday < $display->minwday) {
 123         $startwday += 7;
 124     }
 125
 126     // TODO: THIS IS TEMPORARY CODE!
 127     // [pj] I was just reading through this and realized that I when writing this code I was probably
 128     // asking for trouble, as all these time manipulations seem to be unnecessary and a simple
 129     // make_timestamp would accomplish the same thing. So here goes a test:
 130     //$test_start = make_timestamp($y, $m, 1);
 131     //$test_end   = make_timestamp($y, $m, $display->maxdays, 23, 59, 59);
 132     //if($test_start != usertime($display->tstart) - dst_offset_on($display->tstart)) {
 133         //notify('Failed assertion in calendar/lib.php line 126; display->tstart = '.$display->tstart.', dst_offset = '.dst_offset_on($display->tstart).', usertime = '.usertime($display->tstart).', make_t = '.$test_start);
 134     //}
 135     //if($test_end != usertime($display->tend) - dst_offset_on($display->tend)) {
 136         //notify('Failed assertion in calendar/lib.php line 130; display->tend = '.$display->tend.', dst_offset = '.dst_offset_on($display->tend).', usertime = '.usertime($display->tend).', make_t = '.$test_end);
 137     //}
 138
 139
 140     // Get the events matching our criteria. Don't forget to offset the timestamps for the user's TZ!
 141     $whereclause = calendar_sql_where(
 142         usertime($display->tstart) - dst_offset_on($display->tstart),
 143         usertime($display->tend) - dst_offset_on($display->tend),
 144         $users, $groups, $courses);
 145
 146     if($whereclause === false) {
 147         $events = array();
 148     }
 149     else {
 150         $events = get_records_select('event', $whereclause, 'timestart');
 151     }
 152
 153     // Set event course class for course events
 154     if (!empty($events)) {
 155         foreach ($events as $eventid => $event) {
 156             if($event->courseid != 0 && $event->courseid != SITEID && $event->groupid == 0) {
 157                 $event->class = 'event_course'.array_search($event->courseid, $courses) % CALENDAR_MAXCOURSES;
 158             }
 159             if (!empty($event->modulename)) {
 160                 $cm = get_coursemodule_from_instance($event->modulename, $event->instance);
 161                 if (!groups_course_module_visible($cm)) {
 162                     unset($events[$eventid]);
 163                 }
 164             }
 165         }
 166     }
 167
 168     // This is either a genius idea or an idiot idea: in order to not complicate things, we use this rule: if, after
 169     // possibly removing SITEID from $courses, there is only one course left, then clicking on a day in the month
 170     // will also set the $SESSION->cal_courses_shown variable to that one course. Otherwise, we 'd need to add extra
 171     // arguments to this function.
 172
 173     $morehref = '';
 174     if(!empty($courses)) {
 175         $courses = array_diff($courses, array(SITEID));
 176         if(count($courses) == 1) {
 177             $morehref = '&amp;course='.reset($courses);
 178         }
 179     }
 180
 181     // We want to have easy access by day, since the display is on a per-day basis.
 182     // Arguments passed by reference.
 183     //calendar_events_by_day($events, $display->tstart, $eventsbyday, $durationbyday, $typesbyday);
 184     calendar_events_by_day($events, $m, $y, $eventsbyday, $durationbyday, $typesbyday, $courses);
 185
 186     //Accessibility: added summary and <abbr> elements.
 187     ///global $CALENDARDAYS; appears to be broken.
 188     $days_title = array('sunday','monday','tuesday','wednesday','thursday','friday','saturday');
 189
 190     $summary = get_string('calendarheading', 'calendar', userdate(make_timestamp($y, $m), get_string('strftimemonthyear')));
 191     $summary = get_string('tabledata', 'access', $summary);
 192     $content .= '<table class="minicalendar" summary="'.$summary.'">'; // Begin table
 193     $content .= '<tr class="weekdays">'; // Header row: day names
 194
 195     // Print out the names of the weekdays
 196     $days = array('sun', 'mon', 'tue', 'wed', 'thu', 'fri', 'sat');
 197     for($i = $display->minwday; $i <= $display->maxwday; ++$i) {
 198         // This uses the % operator to get the correct weekday no matter what shift we have
 199         // applied to the $display->minwday : $display->maxwday range from the default 0 : 6
 200         $content .= '<th scope="col"><abbr title="'. get_string($days_title[$i % 7], 'calendar') .'">'.
 201             get_string($days[$i % 7], 'calendar') ."</abbr></th>\n";
 202     }
 203
 204     $content .= '</tr><tr>'; // End of day names; prepare for day numbers
 205
 206     // For the table display. $week is the row; $dayweek is the column.
 207     $dayweek = $startwday;
 208
 209     // Paddding (the first week may have blank days in the beginning)
 210     for($i = $display->minwday; $i < $startwday; ++$i) {
 211         $content .= '<td class="dayblank">&nbsp;</td>'."\n";
 212     }
 213
 214     // Now display all the calendar
 215     for($day = 1; $day <= $display->maxdays; ++$day, ++$dayweek) {
 216         if($dayweek > $display->maxwday) {
 217             // We need to change week (table row)
 218             $content .= '</tr><tr>';
 219             $dayweek = $display->minwday;
 220         }
 221
 222         // Reset vars
 223         $cell = '';
 224         if(CALENDAR_WEEKEND & (1 << ($dayweek % 7))) {
 225             // Weekend. This is true no matter what the exact range is.
 226             $class = 'weekend day';
 227         }
 228         else {
 229             // Normal working day.
 230             $class = 'day';
 231         }
 232
 233         // Special visual fx if an event is defined
 234         if(isset($eventsbyday[$day])) {
 235             $dayhref = calendar_get_link_href(CALENDAR_URL.'view.php?view=day'.$morehref.'&amp;', $day, $m, $y);
 236
 237             // OverLib popup
 238             $popupcontent = '';
 239             foreach($eventsbyday[$day] as $eventid) {
 240                 if (!isset($events[$eventid])) {
 241                     continue;
 242                 }
 243                 $event = $events[$eventid];
 244                 if(!empty($event->modulename)) {
 245                     $popupicon = $CFG->modpixpath.'/'.$event->modulename.'/icon.gif';
 246                     $popupalt  = $event->modulename;
 247
 248                 } else if ($event->courseid == SITEID) {                                // Site event
 249                     $popupicon = $CFG->pixpath.'/c/site.gif';
 250                     $popupalt  = '';
 251                 } else if ($event->courseid != 0 && $event->courseid != SITEID && $event->groupid == 0) {      // Course event
 252                     $popupicon = $CFG->pixpath.'/c/course.gif';
 253                     $popupalt  = '';
 254                 } else if ($event->groupid) {                                      // Group event
 255                     $popupicon = $CFG->pixpath.'/c/group.gif';
 256                     $popupalt  = '';
 257                 } else if ($event->userid) {                                       // User event
 258                     $popupicon = $CFG->pixpath.'/c/user.gif';
 259                     $popupalt  = '';
 260                 }
 261                 $popupcontent .= '<div><img class="icon" src="'.$popupicon.'" alt="'.$popupalt.'" /><a href="'.$dayhref.'#event_'.$event->id.'">'.format_string($event->name, true).'</a></div>';
 262             }
 263
 264             //Accessibility: functionality moved to calendar_get_popup.
 265             if($display->thismonth && $day == $d) {
 266                 $popup = calendar_get_popup(true, $events[$eventid]->timestart, $popupcontent);
 267             } else {
 268                 $popup = calendar_get_popup(false, $events[$eventid]->timestart, $popupcontent);
 269             }
 270
 271             // Class and cell content
 272             if(isset($typesbyday[$day]['startglobal'])) {
 273                 $class .= ' event_global';
 274             }
 275             else if(isset($typesbyday[$day]['startcourse'])) {
 276                 $class .= ' event_course';
 277             }
 278             else if(isset($typesbyday[$day]['startgroup'])) {
 279                 $class .= ' event_group';
 280             }
 281             else if(isset($typesbyday[$day]['startuser'])) {
 282                 $class .= ' event_user';
 283             }
 284             $cell = '<a href="'.$dayhref.'" '.$popup.'>'.$day.'</a>';
 285         }
 286         else {
 287             $cell = $day;
 288         }
 289
 290         if(isset($typesbyday[$day]['durationglobal'])) {
 291             $class .= ' duration_global';
 292         }
 293         else if(isset($typesbyday[$day]['durationcourse'])) {
 294             $class .= ' duration_course';
 295         }
 296         else if(isset($typesbyday[$day]['durationgroup'])) {
 297             $class .= ' duration_group';
 298         }
 299         else if(isset($typesbyday[$day]['durationuser'])) {
 300             $class .= ' duration_user';
 301         }
 302
 303         // If event has a class set then add it to the table day <td> tag
 304         // Note: only one colour for minicalendar
 305         if(isset($eventsbyday[$day])) {
 306             foreach($eventsbyday[$day] as $eventid) {
 307                 if (!isset($events[$eventid])) {
 308                     continue;
 309                 }
 310                 $event = $events[$eventid];
 311                 if (!empty($event->class)) {
 312                     $class .= ' '.$event->class;
 313                 }
 314                 break;
 315             }
 316         }
 317
 318         // Special visual fx for today
 319         //Accessibility: hidden text for today, and popup.
 320         if($display->thismonth && $day == $d) {
 321             $class .= ' today';
 322             $today = get_string('today', 'calendar').' '.userdate(time(), get_string('strftimedayshort'));
 323
 324             if(! isset($eventsbyday[$day])) {
 325                 $class .= ' eventnone';
 326                 $popup = calendar_get_popup(true, false);
 327                 $cell = '<a href="#" '.$popup.'>'.$day.'</a>';
 328             }
 329             $cell = '<span class="accesshide">'.$today.' </span>'.$cell;
 330         }
 331
 332         // Just display it
 333         if(!empty($class)) {
 334             $class = ' class="'.$class.'"';
 335         }
 336         $content .= '<td'.$class.'>'.$cell."</td>\n";
 337     }
 338
 339     // Paddding (the last week may have blank days at the end)
 340     for($i = $dayweek; $i <= $display->maxwday; ++$i) {
 341         $content .= '<td class="dayblank">&nbsp;</td>';
 342     }
 343     $content .= '</tr>'; // Last row ends
 344
 345     $content .= '</table>'; // Tabular display of days ends
 346
 347     return $content;
 348 }
 349
 350 /**
 351  * calendar_get_popup, called at multiple points in from calendar_get_mini.
 352  *        Copied and modified from calendar_get_mini.
 353  * @uses OverLib popup.
 354  * @param $is_today bool, false except when called on the current day.
 355  * @param $event_timestart mixed, $events[$eventid]->timestart, OR false if there are no events.
 356  * @param $popupcontent string.
 357  * @return $popup string, contains onmousover and onmouseout events.
 358  */
 359 function calendar_get_popup($is_today, $event_timestart, $popupcontent='') {
 360     $popupcaption = '';
 361     if($is_today) {
 362         $popupcaption = get_string('today', 'calendar').' ';
 363     }
 364     if (false === $event_timestart) {
 365         $popupcaption .= userdate(time(), get_string('strftimedayshort'));
 366         $popupcontent = get_string('eventnone', 'calendar');
 367
 368     } else {
 369         $popupcaption .= get_string('eventsfor', 'calendar', userdate($event_timestart, get_string('strftimedayshort')));
 370     }
 371     $popupcontent = str_replace("'", "\'", htmlspecialchars($popupcontent));
 372     $popupcaption = str_replace("'", "\'", htmlspecialchars($popupcaption));
 373     $popup = 'onmouseover="return overlib(\''.$popupcontent.'\', CAPTION, \''.$popupcaption.'\');" onmouseout="return nd();"';
 374     return $popup;
 375 }
 376
 377 function calendar_get_upcoming($courses, $groups, $users, $daysinfuture, $maxevents, $fromtime=0) {
 378     global $CFG;
 379
 380     $display = &new stdClass;
 381     $display->range = $daysinfuture; // How many days in the future we 'll look
 382     $display->maxevents = $maxevents;
 383
 384     $output = array();
 385
 386     // Prepare "course caching", since it may save us a lot of queries
 387     $coursecache = array();
 388
 389     $processed = 0;
 390     $now = time(); // We 'll need this later
 391     $usermidnighttoday = usergetmidnight($now);
 392
 393     if ($fromtime) {
 394         $display->tstart = $fromtime;
 395     } else {
 396         $display->tstart = $usermidnighttoday;
 397     }
 398
 399     // This works correctly with respect to the user's DST, but it is accurate
 400     // only because $fromtime is always the exact midnight of some day!
 401     $display->tend = usergetmidnight($display->tstart + DAYSECS * $display->range + 3 * HOURSECS) - 1;
 402
 403     // Get the events matching our criteria
 404     $whereclause = calendar_sql_where($display->tstart, $display->tend, $users, $groups, $courses);
 405     if ($whereclause === false) {
 406         $events = false;
 407     } else {
 408         $events = get_records_select('event', $whereclause, 'timestart');
 409     }
 410
 411     // This is either a genius idea or an idiot idea: in order to not complicate things, we use this rule: if, after
 412     // possibly removing SITEID from $courses, there is only one course left, then clicking on a day in the month
 413     // will also set the $SESSION->cal_courses_shown variable to that one course. Otherwise, we 'd need to add extra
 414     // arguments to this function.
 415
 416     $morehref = '';
 417     if(!empty($courses)) {
 418         $courses = array_diff($courses, array(SITEID));
 419         if(count($courses) == 1) {
 420             $morehref = '&amp;course='.reset($courses);
 421         }
 422     }
 423
 424     if($events !== false) {
 425
 426         foreach($events as $event) {
 427             if(!empty($event->modulename)) {
 428                 $mod = get_coursemodule_from_instance($event->modulename, $event->instance);
 429                 if (!groups_course_module_visible($mod)) {
 430                     continue;
 431                 }
 432             }
 433
 434             if($processed >= $display->maxevents) {
 435                 break;
 436             }
 437
 438             $event->time = calendar_format_event_time($event, $now, $morehref);
 439             $output[] = $event;
 440             ++$processed;
 441         }
 442     }
 443     return $output;
 444 }
 445
 446 function calendar_add_event_metadata($event) {
 447     global $CFG;
 448
 449     //Support multilang in event->name
 450     $event->name = format_string($event->name,true);
 451
 452     if(!empty($event->modulename)) {                                // Activity event
 453         // The module name is set. I will assume that it has to be displayed, and
 454         // also that it is an automatically-generated event. And of course that the
 455         // fields for get_coursemodule_from_instance are set correctly.
 456         $module = calendar_get_module_cached($coursecache, $event->modulename, $event->instance);
 457
 458         if ($module === false) {
 459             return;
 460         }
 461
 462         $modulename = get_string('modulename', $event->modulename);
 463         $eventtype = get_string($event->eventtype, $event->modulename);
 464         $icon = $CFG->modpixpath.'/'.$event->modulename.'/icon.gif';
 465
 466         $event->icon = '<img height="16" width="16" src="'.$icon.'" alt="'.$eventtype.'" title="'.$modulename.'" style="vertical-align: middle;" />';
 467         $event->referer = '<a href="'.$CFG->wwwroot.'/mod/'.$event->modulename.'/view.php?id='.$module->id.'">'.$event->name.'</a>';
 468         $event->courselink = '<a href="'.$CFG->wwwroot.'/course/view.php?id='.$module->course.'">'.$coursecache[$module->course]->fullname.'</a>';
 469         $event->cmid = $module->id;
 470
 471
 472     } else if($event->courseid == SITEID) {                              // Site event
 473         $event->icon = '<img height="16" width="16" src="'.$CFG->pixpath.'/c/site.gif" alt="'.get_string('globalevent', 'calendar').'" style="vertical-align: middle;" />';
 474         $event->cssclass = 'event_global';
 475     } else if($event->courseid != 0 && $event->courseid != SITEID && $event->groupid == 0) {          // Course event
 476         calendar_get_course_cached($coursecache, $event->courseid);
 477         $event->icon = '<img height="16" width="16" src="'.$CFG->pixpath.'/c/course.gif" alt="'.get_string('courseevent', 'calendar').'" style="vertical-align: middle;" />';
 478         $event->courselink = '<a href="'.$CFG->wwwroot.'/course/view.php?id='.$event->courseid.'">'.$coursecache[$event->courseid]->fullname.'</a>';
 479         $event->cssclass = 'event_course';
 480     } else if ($event->groupid) {                                    // Group event
 481         $event->icon = '<img height="16" width="16" src="'.$CFG->pixpath.'/c/group.gif" alt="'.get_string('groupevent', 'calendar').'" style="vertical-align: middle;" />';
 482         $event->cssclass = 'event_group';
 483     } else if($event->userid) {                                      // User event
 484         $event->icon = '<img height="16" width="16" src="'.$CFG->pixpath.'/c/user.gif" alt="'.get_string('userevent', 'calendar').'" style="vertical-align: middle;" />';
 485         $event->cssclass = 'event_user';
 486     }
 487     return $event;
 488 }
 489
 490 function calendar_print_event($event) {
 491     global $CFG, $USER;
 492
 493     static $strftimetime;
 494
 495     $event = calendar_add_event_metadata($event);
 496     echo '<a name="event_'.$event->id.'"></a><table class="event" cellspacing="0">';
 497     echo '<tr><td class="picture">';
 498     if (!empty($event->icon)) {
 499         echo $event->icon;
 500     } else {
 501         print_spacer(16,16);
 502     }
 503     echo '</td>';
 504     echo '<td class="topic">';
 505
 506     if (!empty($event->referer)) {
 507         echo '<div class="referer">'.$event->referer.'</div>';
 508     } else {
 509         echo '<div class="name">'.$event->name."</div>";
 510     }
 511     if (!empty($event->courselink)) {
 512         echo '<div class="course">'.$event->courselink.' </div>';
 513     }
 514     if (!empty($event->time)) {
 515         echo '<span class="date">'.$event->time.'</span>';
 516     } else {
 517         echo '<span class="date">'.calendar_time_representation($event->timestart).'</span>';
 518     }
 519
 520     echo '</td></tr>';
 521     echo '<tr><td class="side">&nbsp;</td>';
 522
 523     // If event has a class set then add it to the event <td> tag
 524     $eventclass='';
 525     if (!empty($event->class)) {
 526         $eventclass = ' '.$event->class;
 527     }
 528
 529     echo '<td class="description '.$event->cssclass.$eventclass.'">';
 530     echo format_text($event->description, FORMAT_HTML);
 531     if (calendar_edit_event_allowed($event)) {
 532         echo '<div class="commands">';
 533         $calendarcourseid = '';
 534         if (!empty($event->calendarcourseid)) {
 535             $calendarcourseid = '&amp;course='.$event->calendarcourseid;
 536         }
 537         if (empty($event->cmid)) {
 538             $editlink   = CALENDAR_URL.'event.php?action=edit&amp;id='.$event->id.$calendarcourseid;
 539             $deletelink = CALENDAR_URL.'event.php?action=delete&amp;id='.$event->id.$calendarcourseid;
 540         } else {
 541             $editlink   = $CFG->wwwroot.'/course/mod.php?update='.$event->cmid.'&amp;return=true&amp;sesskey='.$USER->sesskey;
 542             $deletelink = $CFG->wwwroot.'/course/mod.php?delete='.$event->cmid.'&amp;sesskey='.$USER->sesskey;;
 543         }
 544         echo ' <a href="'.$editlink.'"><img
 545                   src="'.$CFG->pixpath.'/t/edit.gif" alt="'.get_string('tt_editevent', 'calendar').'"
 546                   title="'.get_string('tt_editevent', 'calendar').'" /></a>';
 547         echo ' <a href="'.$deletelink.'"><img
 548                   src="'.$CFG->pixpath.'/t/delete.gif" alt="'.get_string('tt_deleteevent', 'calendar').'"
 549                   title="'.get_string('tt_deleteevent', 'calendar').'" /></a>';
 550         echo '</div>';
 551     }
 552     echo '</td></tr></table>';
 553
 554 }
 555
 556 function calendar_sql_where($tstart, $tend, $users, $groups, $courses, $withduration=true, $ignorehidden=true) {
 557     $whereclause = '';
 558     // Quick test
 559     if(is_bool($users) && is_bool($groups) && is_bool($courses)) {
 560         return false;
 561     }
 562
 563     if(is_array($users) && !empty($users)) {
 564         // Events from a number of users
 565         if(!empty($whereclause)) $whereclause .= ' OR';
 566         $whereclause .= ' (userid IN ('.implode(',', $users).') AND courseid = 0 AND groupid = 0)';
 567     }
 568     else if(is_numeric($users)) {
 569         // Events from one user
 570         if(!empty($whereclause)) $whereclause .= ' OR';
 571         $whereclause .= ' (userid = '.$users.' AND courseid = 0 AND groupid = 0)';
 572     }
 573     else if($users === true) {
 574         // Events from ALL users
 575         if(!empty($whereclause)) $whereclause .= ' OR';
 576         $whereclause .= ' (userid != 0 AND courseid = 0 AND groupid = 0)';
 577     }
 578     else if($users === false) {
 579         // No user at all, do nothing
 580     }
 581
 582     if(is_array($groups) && !empty($groups)) {
 583         // Events from a number of groups
 584         if(!empty($whereclause)) $whereclause .= ' OR';
 585         $whereclause .= ' groupid IN ('.implode(',', $groups).')';
 586     }
 587     else if(is_numeric($groups)) {
 588         // Events from one group
 589         if(!empty($whereclause)) $whereclause .= ' OR ';
 590         $whereclause .= ' groupid = '.$groups;
 591     }
 592     else if($groups === true) {
 593         // Events from ALL groups
 594         if(!empty($whereclause)) $whereclause .= ' OR ';
 595         $whereclause .= ' groupid != 0';
 596     }
 597     // boolean false (no groups at all): we don't need to do anything
 598
 599     if(is_array($courses)) {
 600         // A number of courses (maybe none at all!)
 601         if(!empty($courses)) {
 602             if(!empty($whereclause)) {
 603                 $whereclause .= ' OR';
 604             }
 605             $whereclause .= ' (groupid = 0 AND courseid IN ('.implode(',', $courses).'))';
 606         }
 607         else {
 608             // This means NO courses, not that we don't care!
 609             // No need to do anything
 610         }
 611     }
 612     else if(is_numeric($courses)) {
 613         // One course
 614         if(!empty($whereclause)) $whereclause .= ' OR';
 615         $whereclause .= ' (groupid = 0 AND courseid = '.$courses.')';
 616     }
 617     else if($courses === true) {
 618         // Events from ALL courses
 619         if(!empty($whereclause)) $whereclause .= ' OR';
 620         $whereclause .= ' (groupid = 0 AND courseid != 0)';
 621     }
 622
 623     // Security check: if, by now, we have NOTHING in $whereclause, then it means
 624     // that NO event-selecting clauses were defined. Thus, we won't be returning ANY
 625     // events no matter what. Allowing the code to proceed might return a completely
 626     // valid query with only time constraints, thus selecting ALL events in that time frame!
 627     if(empty($whereclause)) {
 628         return false;
 629     }
 630
 631     if($withduration) {
 632         $timeclause = '(timestart >= '.$tstart.' OR timestart + timeduration > '.$tstart.') AND timestart <= '.$tend;
 633     }
 634     else {
 635         $timeclause = 'timestart >= '.$tstart.' AND timestart <= '.$tend;
 636     }
 637     if(!empty($whereclause)) {
 638         // We have additional constraints
 639         $whereclause = $timeclause.' AND ('.$whereclause.')';
 640     }
 641     else {
 642         // Just basic time filtering
 643         $whereclause = $timeclause;
 644     }
 645
 646     if ($ignorehidden) {
 647         $whereclause .= ' AND visible = 1';
 648     }
 649
 650     return $whereclause;
 651 }
 652
 653 function calendar_top_controls($type, $data) {
 654     global $CFG, $CALENDARDAYS, $THEME;
 655     $content = '';
 656     if(!isset($data['d'])) {
 657         $data['d'] = 1;
 658     }
 659
 660     // Ensure course id passed if relevant
 661     // Required due to changes in view/lib.php mainly (calendar_session_vars())
 662     $courseid = '';
 663     if (!empty($data['id'])) {
 664         $courseid = '&amp;course='.$data['id'];
 665     }
 666
 667     if(!checkdate($data['m'], $data['d'], $data['y'])) {
 668         $time = time();
 669     }
 670     else {
 671         $time = make_timestamp($data['y'], $data['m'], $data['d']);
 672     }
 673     $date = usergetdate($time);
 674
 675     $data['m'] = $date['mon'];
 676     $data['y'] = $date['year'];
 677
 678     //Accessibility: calendar block controls, replaced <table> with <div>.
 679     //$nexttext = link_arrow_right(get_string('monthnext', 'access'), $url='', $accesshide=true);
 680     //$prevtext = link_arrow_left(get_string('monthprev', 'access'), $url='', $accesshide=true);
 681
 682     switch($type) {
 683         case 'frontpage':
 684             list($prevmonth, $prevyear) = calendar_sub_month($data['m'], $data['y']);
 685             list($nextmonth, $nextyear) = calendar_add_month($data['m'], $data['y']);
 686             $nextlink = calendar_get_link_next(get_string('monthnext', 'access'), 'index.php?', 0, $nextmonth, $nextyear, $accesshide=true);
 687             $prevlink = calendar_get_link_previous(get_string('monthprev', 'access'), 'index.php?', 0, $prevmonth, $prevyear, true);
 688             $content .= "\n".'<div class="calendar-controls">'. $prevlink;
 689             $content .= '<span class="hide"> | </span><span class="current"><a href="'.calendar_get_link_href(CALENDAR_URL.'view.php?view=month'.$courseid.'&amp;', 1, $data['m'], $data['y']).'">'.userdate($time, get_string('strftimemonthyear')).'</a></span>';
 690             $content .= '<span class="hide"> | </span>'. $nextlink ."\n";
 691             $content .= "<span class=\"clearer\"><!-- --></span></div>\n";
 692         break;
 693         case 'course':
 694             list($prevmonth, $prevyear) = calendar_sub_month($data['m'], $data['y']);
 695             list($nextmonth, $nextyear) = calendar_add_month($data['m'], $data['y']);
 696             $nextlink = calendar_get_link_next(get_string('monthnext', 'access'), 'view.php?id='.$data['id'].'&amp;', 0, $nextmonth, $nextyear, $accesshide=true);
 697             $prevlink = calendar_get_link_previous(get_string('monthprev', 'access'), 'view.php?id='.$data['id'].'&amp;', 0, $prevmonth, $prevyear, true);
 698             $content .= "\n".'<div class="calendar-controls">'. $prevlink;
 699             $content .= '<span class="hide"> | </span><span class="current"><a href="'.calendar_get_link_href(CALENDAR_URL.'view.php?view=month'.$courseid.'&amp;', 1, $data['m'], $data['y']).'">'.userdate($time, get_string('strftimemonthyear')).'</a></span>';
 700             $content .= '<span class="hide"> | </span>'. $nextlink ."\n";
 701             $content .= "<span class=\"clearer\"><!-- --></span></div>\n";
 702         break;
 703         case 'upcoming':
 704             $content .= '<div style="text-align: center;"><a href="'.CALENDAR_URL.'view.php?view=upcoming"'.$courseid.'>'.userdate($time, get_string('strftimemonthyear'))."</a></div>\n";
 705         break;
 706         case 'display':
 707             $content .= '<div style="text-align: center;"><a href="'.calendar_get_link_href(CALENDAR_URL.'view.php?view=month'.$courseid.'&amp;', 1, $data['m'], $data['y']).'">'.userdate($time, get_string('strftimemonthyear'))."</a></div>\n";
 708         break;
 709         case 'month':
 710             list($prevmonth, $prevyear) = calendar_sub_month($data['m'], $data['y']);
 711             list($nextmonth, $nextyear) = calendar_add_month($data['m'], $data['y']);
 712             $prevdate = make_timestamp($prevyear, $prevmonth, 1);
 713             $nextdate = make_timestamp($nextyear, $nextmonth, 1);
 714             $content .= "\n".'<div class="calendar-controls">';
 715             $content .= calendar_get_link_previous(userdate($prevdate, get_string('strftimemonthyear')), 'view.php?view=month'.$courseid.'&amp;', 1, $prevmonth, $prevyear);
 716             $content .= '<span class="hide"> | </span><span class="current">'.userdate($time, get_string('strftimemonthyear'))."</span>\n";
 717             $content .= '<span class="hide"> | </span>'.calendar_get_link_next(userdate($nextdate, get_string('strftimemonthyear')), 'view.php?view=month'.$courseid.'&amp;', 1, $nextmonth, $nextyear);
 718             $content .= "<span class=\"clearer\"><!-- --></span></div>\n";
 719         break;
 720         case 'day':
 721             $data['d'] = $date['mday']; // Just for convenience
 722             $prevdate = usergetdate(make_timestamp($data['y'], $data['m'], $data['d'] - 1));
 723             $nextdate = usergetdate(make_timestamp($data['y'], $data['m'], $data['d'] + 1));
 724             $prevname = calendar_wday_name($CALENDARDAYS[$prevdate['wday']]);
 725             $nextname = calendar_wday_name($CALENDARDAYS[$nextdate['wday']]);
 726             $content .= "\n".'<div class="calendar-controls">';
 727             $content .= calendar_get_link_previous($prevname, 'view.php?view=day'.$courseid.'&amp;', $prevdate['mday'], $prevdate['mon'], $prevdate['year']);
 728
 729             // Get the format string
 730             $text = get_string('strftimedaydate');
 731             /*
 732             // Regexp hackery to make a link out of the month/year part
 733             $text = ereg_replace('(%B.+%Y|%Y.+%B|%Y.+%m[^ ]+)', '<a href="'.calendar_get_link_href('view.php?view=month&amp;', 1, $data['m'], $data['y']).'">\\1</a>', $text);
 734             $text = ereg_replace('(F.+Y|Y.+F|Y.+m[^ ]+)', '<a href="'.calendar_get_link_href('view.php?view=month&amp;', 1, $data['m'], $data['y']).'">\\1</a>', $text);
 735             */
 736             // Replace with actual values and lose any day leading zero
 737             $text = userdate($time, $text);
 738             // Print the actual thing
 739             $content .= '<span class="hide"> | </span><span class="current">'.$text.'</span>';
 740
 741             $content .= '<span class="hide"> | </span>'. calendar_get_link_next($nextname, 'view.php?view=day'.$courseid.'&amp;', $nextdate['mday'], $nextdate['mon'], $nextdate['year']);
 742             $content .= "<span class=\"clearer\"><!-- --></span></div>\n";
 743         break;
 744     }
 745     return $content;
 746 }
 747
 748 function calendar_filter_controls($type, $vars = NULL, $course = NULL, $courses = NULL) {
 749     global $CFG, $SESSION, $USER;
 750
 751     $groupevents = true;
 752     $getvars = '';
 753
 754     $id = optional_param( 'id',0,PARAM_INT );
 755
 756     switch($type) {
 757         case 'event':
 758         case 'upcoming':
 759         case 'day':
 760         case 'month':
 761             $getvars = '&amp;from='.$type;
 762         break;
 763         case 'course':
 764             if ($id > 0) {
 765                 $getvars = '&amp;from=course&amp;id='.$id;
 766             } else {
 767                 $getvars = '&amp;from=course';
 768             }
 769             if (isset($course->groupmode) and $course->groupmode == NOGROUPS and $course->groupmodeforce) {
 770                 $groupevents = false;
 771             }
 772         break;
 773     }
 774
 775     if (!empty($vars)) {
 776         $getvars .= '&amp;'.$vars;
 777     }
 778
 779     $content = '<table>';
 780
 781     $content .= '<tr>';
 782     if($SESSION->cal_show_global) {
 783         $content .= '<td class="eventskey event_global" style="width: 11px;"><img src="'.$CFG->pixpath.'/t/hide.gif" class="iconsmall" alt="'.get_string('hide').'" title="'.get_string('tt_hideglobal', 'calendar').'" style="cursor:pointer" onclick="location.href='."'".CALENDAR_URL.'set.php?var=showglobal'.$getvars."'".'" /></td>';
 784         $content .= '<td><a href="'.CALENDAR_URL.'set.php?var=showglobal'.$getvars.'" title="'.get_string('tt_hideglobal', 'calendar').'">'.get_string('global', 'calendar').'</a></td>'."\n";
 785     }
 786     else {
 787         $content .= '<td style="width: 11px;"><img src="'.$CFG->pixpath.'/t/show.gif" class="iconsmall" alt="'.get_string('show').'" title="'.get_string('tt_showglobal', 'calendar').'" style="cursor:pointer" onclick="location.href='."'".CALENDAR_URL.'set.php?var=showglobal'.$getvars."'".'" /></td>';
 788         $content .= '<td><a href="'.CALENDAR_URL.'set.php?var=showglobal'.$getvars.'" title="'.get_string('tt_showglobal', 'calendar').'">'.get_string('global', 'calendar').'</a></td>'."\n";
 789     }
 790     $tr = '';
 791
 792     if(!empty($USER->id) && !isguest()) {
 793
 794         $content .= $tr;
 795         $tr = $tr ? '' : "</tr>\n<tr>";
 796
 797         if($groupevents) {
 798
 799             // This course MIGHT have group events defined, so show the filter
 800             if($SESSION->cal_show_groups) {
 801                 $content .= '<td class="eventskey event_group" style="width: 11px;"><img src="'.$CFG->pixpath.'/t/hide.gif" class="iconsmall" alt="'.get_string('hide').'" title="'.get_string('tt_hidegroups', 'calendar').'" style="cursor:pointer" onclick="location.href='."'".CALENDAR_URL.'set.php?var=showgroups'.$getvars."'".'" /></td>';
 802                 $content .= '<td><a href="'.CALENDAR_URL.'set.php?var=showgroups'.$getvars.'" title="'.get_string('tt_hidegroups', 'calendar').'">'.get_string('group', 'calendar').'</a></td>'."\n";
 803             } else {
 804                 $content .= '<td style="width: 11px;"><img src="'.$CFG->pixpath.'/t/show.gif" class="iconsmall" alt="'.get_string('show').'" title="'.get_string('tt_showgroups', 'calendar').'" style="cursor:pointer" onclick="location.href='."'".CALENDAR_URL.'set.php?var=showgroups'.$getvars."'".'" /></td>';
 805                 $content .= '<td><a href="'.CALENDAR_URL.'set.php?var=showgroups'.$getvars.'" title="'.get_string('tt_showgroups', 'calendar').'">'.get_string('group', 'calendar').'</a></td>'."\n";
 806             }
 807         } else {
 808
 809             // This course CANNOT have group events, so lose the filter
 810             $content .= '<td style="width: 11px;"></td><td>&nbsp;</td>'."\n";
 811         }
 812
 813         $content .= $tr;
 814         $tr = $tr ? '' : "</tr>\n<tr>";
 815
 816         if ($SESSION->cal_show_user) {
 817             $content .= '<td class="eventskey event_user" style="width: 11px;"><img src="'.$CFG->pixpath.'/t/hide.gif" class="iconsmall" alt="'.get_string('hide').'" title="'.get_string('tt_hideuser', 'calendar').'" style="cursor:pointer" onclick="location.href='."'".CALENDAR_URL.'set.php?var=showuser'.$getvars."'".'" /></td>';
 818             $content .= '<td><a href="'.CALENDAR_URL.'set.php?var=showuser'.$getvars.'" title="'.get_string('tt_hideuser', 'calendar').'">'.get_string('user', 'calendar').'</a></td>'."\n";
 819         } else {
 820             $content .= '<td style="width: 11px;"><img src="'.$CFG->pixpath.'/t/show.gif" class="iconsmall" alt="'.get_string('show').'" title="'.get_string('tt_showuser', 'calendar').'" style="cursor:pointer" onclick="location.href='."'".CALENDAR_URL.'set.php?var=showuser'.$getvars."'".'" /></td>';
 821             $content .= '<td><a href="'.CALENDAR_URL.'set.php?var=showuser'.$getvars.'" title="'.get_string('tt_showuser', 'calendar').'">'.get_string('user', 'calendar').'</a></td>'."\n";
 822         }
 823     }
 824
 825     // Remove global SITE ID from courses array as do not want to display this
 826     if (!empty($courses)) {
 827         $key = array_search(SITEID, $courses);
 828         if ($key !== false) {
 829             unset($courses[$key]);
 830         }
 831     }
 832
 833     if (empty($courses) || count($courses) == 1) {
 834
 835         // If not multiple courses then just display default single course colour highlighting
 836         $content .= $tr;
 837         $tr = $tr ? '' : "</tr>\n<tr>";
 838
 839         if($SESSION->cal_show_course) {
 840             $content .= '<td class="eventskey event_course" style="width: 11px;"><img src="'.$CFG->pixpath.'/t/hide.gif" class="iconsmall" alt="'.get_string('hide').'" title="'.get_string('tt_hidecourse', 'calendar').'" style="cursor:pointer" onclick="location.href='."'".CALENDAR_URL.'set.php?var=showcourses'.$getvars."'".'" /></td>';
 841             $content .= '<td><a href="'.CALENDAR_URL.'set.php?var=showcourses'.$getvars.'" title="'.get_string('tt_hidecourse', 'calendar').'">'.get_string('course', 'calendar').'</a></td>'."\n";
 842         }
 843         else {
 844             $content .= '<td style="width: 11px;"><img src="'.$CFG->pixpath.'/t/show.gif" class="iconsmall" alt="'.get_string('hide').'" title="'.get_string('tt_showcourse', 'calendar').'" style="cursor:pointer" onclick="location.href='."'".CALENDAR_URL.'set.php?var=showcourses'.$getvars."'".'" /></td>';
 845             $content .= '<td><a href="'.CALENDAR_URL.'set.php?var=showcourses'.$getvars.'" title="'.get_string('tt_showcourse', 'calendar').'">'.get_string('course', 'calendar').'</a></td>'."\n";
 846         }
 847     } else {
 848
 849         // Otherwise display list of course shortnames and relevant colours
 850         // Get list of course shortnames (Limit to 12 for now - who would have more than that?)
 851         $select = 'id in ('.implode(',', $courses).')';
 852         $sort = 'id';
 853         $fields = 'id, shortname';
 854         $courseshortnames = get_records_select('course', $select, $sort, $fields, 0, 12);
 855
 856         for ($i = 0; $i < CALENDAR_MAXCOURSES; $i++) {
 857
 858             // Concatenate shortnames if there are more than 3 courses
 859             $strshortnames = '';
 860             $n = 0;
 861             for ($j = $i; $j < count($courses); $j += CALENDAR_MAXCOURSES) {
 862                 $strshortnames .= ', <a title="" href="'.$CFG->wwwroot.'/course/view.php?id='.$courses[$j].'">'.(!empty($courseshortnames[$courses[$j]]->shortname) ? $courseshortnames[$courses[$j]]->shortname : $courses[$j]).'</a>';
 863                 $n++;
 864             }
 865
 866             if ($n) {
 867
 868                 $content .= $tr;
 869                 $tr = $tr ? '' : "</tr>\n<tr>";
 870
 871                 if ($n < 2) {
 872                     $strcourse = get_string('course', 'calendar');
 873                 } else {
 874                     $strcourse = get_string('courses', 'calendar');
 875                 }
 876
 877                 if($SESSION->cal_show_course) {
 878                     $content .= '<td class="eventskey event_course'.$i.'" style="width: 11px;"><img src="'.$CFG->pixpath.'/t/hide.gif" class="iconsmall" alt="'.get_string('hide').'" title="'.get_string('tt_hidecourse', 'calendar').'" style="cursor:pointer" onclick="location.href='."'".CALENDAR_URL.'set.php?var=showcourses'.$getvars."'".'" /></td>';
 879                     $content .= '<td><a href="'.CALENDAR_URL.'set.php?var=showcourses'.$getvars.'" title="'.get_string('tt_hidecourse', 'calendar').'">'.$strcourse.'</a>: '.substr($strshortnames, 2).'</td>'."\n";
 880                 }
 881                 else {
 882                     $content .= '<td style="width: 11px;"><img src="'.$CFG->pixpath.'/t/show.gif" class="iconsmall" alt="'.get_string('hide').'" title="'.get_string('tt_showcourse', 'calendar').'" style="cursor:pointer" onclick="location.href='."'".CALENDAR_URL.'set.php?var=showcourses'.$getvars."'".'" /></td>';
 883                     $content .= '<td><a href="'.CALENDAR_URL.'set.php?var=showcourses'.$getvars.'" title="'.get_string('tt_showcourse', 'calendar').'">'.$strcourse.'</a>: '.substr($strshortnames, 2).'</td>'."\n";
 884                 }
 885             }
 886         }
 887     }
 888     $content .= "</tr>\n</table>\n";
 889
 890     return $content;
 891 }
 892
 893 function calendar_day_representation($tstamp, $now = false, $usecommonwords = true) {
 894
 895     static $shortformat;
 896     if(empty($shortformat)) {
 897         $shortformat = get_string('strftimedayshort');
 898     }
 899
 900     if($now === false) {
 901         $now = time();
 902     }
 903
 904     // To have it in one place, if a change is needed
 905     $formal = userdate($tstamp, $shortformat);
 906
 907     $datestamp = usergetdate($tstamp);
 908     $datenow   = usergetdate($now);
 909
 910     if($usecommonwords == false) {
 911         // We don't want words, just a date
 912         return $formal;
 913     }
 914     else if($datestamp['year'] == $datenow['year'] && $datestamp['yday'] == $datenow['yday']) {
 915         // Today
 916         return get_string('today', 'calendar');
 917     }
 918     else if(
 919         ($datestamp['year'] == $datenow['year'] && $datestamp['yday'] == $datenow['yday'] - 1 ) ||
 920         ($datestamp['year'] == $datenow['year'] - 1 && $datestamp['mday'] == 31 && $datestamp['mon'] == 12 && $datenow['yday'] == 1)
 921         ) {
 922         // Yesterday
 923         return get_string('yesterday', 'calendar');
 924     }
 925     else if(
 926         ($datestamp['year'] == $datenow['year'] && $datestamp['yday'] == $datenow['yday'] + 1 ) ||
 927         ($datestamp['year'] == $datenow['year'] + 1 && $datenow['mday'] == 31 && $datenow['mon'] == 12 && $datestamp['yday'] == 1)
 928         ) {
 929         // Tomorrow
 930         return get_string('tomorrow', 'calendar');
 931     }
 932     else {
 933         return $formal;
 934     }
 935 }
 936
 937 function calendar_time_representation($time) {
 938     static $langtimeformat = NULL;
 939     if($langtimeformat === NULL) {
 940         $langtimeformat = get_string('strftimetime');
 941     }
 942     $timeformat = get_user_preferences('calendar_timeformat');
 943     if(empty($timeformat)){
 944         $timeformat = get_config(NULL,'calendar_site_timeformat');
 945     }
 946     // The ? is needed because the preference might be present, but empty
 947     return userdate($time, empty($timeformat) ? $langtimeformat : $timeformat);
 948 }
 949
 950 /**
 951  * TODO document
 952  */
 953 function calendar_get_link_href($linkbase, $d, $m, $y) {
 954     if(empty($linkbase)) return '';
 955     $paramstr = '';
 956     if(!empty($d)) $paramstr .= '&amp;cal_d='.$d;
 957     if(!empty($m)) $paramstr .= '&amp;cal_m='.$m;
 958     if(!empty($y)) $paramstr .= '&amp;cal_y='.$y;
 959     if(!empty($paramstr)) $paramstr = substr($paramstr, 5);
 960     return $linkbase.$paramstr;
 961 }
 962
 963 /**
 964  * TODO document
 965  */
 966 function calendar_get_link_tag($text, $linkbase, $d, $m, $y) {
 967     $href = calendar_get_link_href($linkbase, $d, $m, $y);
 968     if(empty($href)) return $text;
 969     return '<a href="'.$href.'">'.$text.'</a>';
 970 }
 971
 972 /**
 973  * Build and return a previous month HTML link, with an arrow.
 974  * @param string $text The text label.
 975  * @param string $linkbase The URL stub.
 976  * @param int $d $m $y Day of month, month and year numbers.
 977  * @param bool $accesshide Default visible, or hide from all except screenreaders.
 978  * @return string HTML string.
 979  */
 980 function calendar_get_link_previous($text, $linkbase, $d, $m, $y, $accesshide=false) {
 981     $href = calendar_get_link_href($linkbase, $d, $m, $y);
 982     if(empty($href)) return $text;
 983     return link_arrow_left($text, $href, $accesshide, 'previous');
 984 }
 985
 986 /**
 987  * Build and return a next month HTML link, with an arrow.
 988  * @param string $text The text label.
 989  * @param string $linkbase The URL stub.
 990  * @param int $d $m $y Day of month, month and year numbers.
 991  * @param bool $accesshide Default visible, or hide from all except screenreaders.
 992  * @return string HTML string.
 993  */
 994 function calendar_get_link_next($text, $linkbase, $d, $m, $y, $accesshide=false) {
 995     $href = calendar_get_link_href($linkbase, $d, $m, $y);
 996     if(empty($href)) return $text;
 997     return link_arrow_right($text, $href, $accesshide, 'next');
 998 }
 999
1000 function calendar_wday_name($englishname) {
1001     return get_string(strtolower($englishname), 'calendar');
1002 }
1003
1004 function calendar_days_in_month($month, $year) {
1005    return intval(date('t', mktime(0, 0, 0, $month, 1, $year)));
1006 }
1007
1008 function calendar_get_sideblock_upcoming($events, $linkhref = NULL) {
1009     $content = '';
1010     $lines = count($events);
1011     if (!$lines) {
1012         return $content;
1013     }
1014
1015     for ($i = 0; $i < $lines; ++$i) {
1016         if (!isset($events[$i]->time)) {   // Just for robustness
1017             continue;
1018         }
1019         $events[$i] = calendar_add_event_metadata($events[$i]);
1020         $content .= '<div class="event"><span class="icon c0">'.$events[$i]->icon.'</span> ';
1021         if (!empty($events[$i]->referer)) {
1022             // That's an activity event, so let's provide the hyperlink
1023             $content .= $events[$i]->referer;
1024         } else {
1025             if(!empty($linkhref)) {
1026                 $ed = usergetdate($events[$i]->timestart);
1027                 $href = calendar_get_link_href(CALENDAR_URL.$linkhref, $ed['mday'], $ed['mon'], $ed['year']);
1028                 $content .= '<a href="'.$href.'#event_'.$events[$i]->id.'">'.$events[$i]->name.'</a>';
1029             }
1030             else {
1031                 $content .= $events[$i]->name;
1032             }
1033         }
1034         $events[$i]->time = str_replace('&raquo;', '<br />&raquo;', $events[$i]->time);
1035         $content .= '<div class="date">'.$events[$i]->time.'</div></div>';
1036         if ($i < $lines - 1) $content .= '<hr />';
1037     }
1038
1039     return $content;
1040 }
1041
1042 function calendar_add_month($month, $year) {
1043     if($month == 12) {
1044         return array(1, $year + 1);
1045     }
1046     else {
1047         return array($month + 1, $year);
1048     }
1049 }
1050
1051 function calendar_sub_month($month, $year) {
1052     if($month == 1) {
1053         return array(12, $year - 1);
1054     }
1055     else {
1056         return array($month - 1, $year);
1057     }
1058 }
1059
1060 function calendar_events_by_day($events, $month, $year, &$eventsbyday, &$durationbyday, &$typesbyday, &$courses) {
1061     $eventsbyday = array();
1062     $typesbyday = array();
1063     $durationbyday = array();
1064
1065     if($events === false) {
1066         return;
1067     }
1068
1069     foreach($events as $event) {
1070
1071         $startdate = usergetdate($event->timestart);
1072         // Set end date = start date if no duration
1073         if ($event->timeduration) {
1074             $enddate   = usergetdate($event->timestart + $event->timeduration - 1);
1075         } else {
1076             $enddate = $startdate;
1077         }
1078
1079         // Simple arithmetic: $year * 13 + $month is a distinct integer for each distinct ($year, $month) pair
1080         if(!($startdate['year'] * 13 + $startdate['mon'] <= $year * 13 + $month) && ($enddate['year'] * 13 + $enddate['mon'] >= $year * 13 + $month)) {
1081             // Out of bounds
1082             continue;
1083         }
1084
1085         $eventdaystart = intval($startdate['mday']);
1086
1087         if($startdate['mon'] == $month && $startdate['year'] == $year) {
1088             // Give the event to its day
1089             $eventsbyday[$eventdaystart][] = $event->id;
1090
1091             // Mark the day as having such an event
1092             if($event->courseid == SITEID && $event->groupid == 0) {
1093                 $typesbyday[$eventdaystart]['startglobal'] = true;
1094                 // Set event class for global event
1095                 $events[$event->id]->class = 'event_global';
1096             }
1097             else if($event->courseid != 0 && $event->courseid != SITEID && $event->groupid == 0) {
1098                 $typesbyday[$eventdaystart]['startcourse'] = true;
1099                 // Set event class for course event
1100                 $events[$event->id]->class = 'event_course'.array_search($event->courseid, $courses) % CALENDAR_MAXCOURSES;
1101             }
1102             else if($event->groupid) {
1103                 $typesbyday[$eventdaystart]['startgroup'] = true;
1104                 // Set event class for group event
1105                 $events[$event->id]->class = 'event_group';
1106             }
1107             else if($event->userid) {
1108                 $typesbyday[$eventdaystart]['startuser'] = true;
1109                 // Set event class for user event
1110                 $events[$event->id]->class = 'event_user';
1111             }
1112         }
1113
1114         if($event->timeduration == 0) {
1115             // Proceed with the next
1116             continue;
1117         }
1118
1119         // The event starts on $month $year or before. So...
1120         $lowerbound = $startdate['mon'] == $month && $startdate['year'] == $year ? intval($startdate['mday']) : 0;
1121
1122         // Also, it ends on $month $year or later...
1123         $upperbound = $enddate['mon'] == $month && $enddate['year'] == $year ? intval($enddate['mday']) : calendar_days_in_month($month, $year);
1124
1125         // Mark all days between $lowerbound and $upperbound (inclusive) as duration
1126         for($i = $lowerbound + 1; $i <= $upperbound; ++$i) {
1127             $durationbyday[$i][] = $event->id;
1128             if($event->courseid == SITEID && $event->groupid == 0) {
1129                 $typesbyday[$i]['durationglobal'] = true;
1130             }
1131             else if($event->courseid != 0 && $event->courseid != SITEID && $event->groupid == 0) {
1132                 $typesbyday[$i]['durationcourse'] = true;
1133             }
1134             else if($event->groupid) {
1135                 $typesbyday[$i]['durationgroup'] = true;
1136             }
1137             else if($event->userid) {
1138                 $typesbyday[$i]['durationuser'] = true;
1139             }
1140         }
1141
1142     }
1143     return;
1144 }
1145
1146 function calendar_get_module_cached(&$coursecache, $modulename, $instance) {
1147     $module = get_coursemodule_from_instance($modulename, $instance);
1148
1149     if($module === false) return false;
1150     if(!calendar_get_course_cached($coursecache, $module->course)) {
1151         return false;
1152     }
1153     return $module;
1154 }
1155
1156 function calendar_get_course_cached(&$coursecache, $courseid) {
1157     global $COURSE;
1158     if (!isset($coursecache[$courseid])) {
1159         if ($courseid == $COURSE->id) {
1160             $coursecache[$courseid] = $COURSE;
1161         } else {
1162             $coursecache[$courseid] = get_record('course', 'id', $courseid);
1163         }
1164     }
1165     return $coursecache[$courseid];
1166 }
1167
1168 function calendar_session_vars() {
1169     global $SESSION, $USER;
1170
1171     if(!empty($USER->id) && isset($USER->realuser) && !isset($SESSION->cal_loggedinas)) {
1172         // We just logged in as someone else, update the filtering
1173         unset($SESSION->cal_users_shown);
1174         unset($SESSION->cal_courses_shown);
1175         $SESSION->cal_loggedinas = true;
1176         if(intval(get_user_preferences('calendar_persistflt', 0))) {
1177             calendar_set_filters_status(get_user_preferences('calendar_savedflt', 0xff));
1178         }
1179     }
1180     else if(!empty($USER->id) && !isset($USER->realuser) && isset($SESSION->cal_loggedinas)) {
1181         // We just logged back to our real self, update again
1182         unset($SESSION->cal_users_shown);
1183         unset($SESSION->cal_courses_shown);
1184         unset($SESSION->cal_loggedinas);
1185         if(intval(get_user_preferences('calendar_persistflt', 0))) {
1186             calendar_set_filters_status(get_user_preferences('calendar_savedflt', 0xff));
1187         }
1188     }
1189
1190     if(!isset($SESSION->cal_course_referer)) {
1191         $SESSION->cal_course_referer = 0;
1192     }
1193     if(!isset($SESSION->cal_show_global)) {
1194         $SESSION->cal_show_global = true;
1195     }
1196     if(!isset($SESSION->cal_show_groups)) {
1197         $SESSION->cal_show_groups = true;
1198     }
1199     if(!isset($SESSION->cal_show_course)) {
1200         $SESSION->cal_show_course = true;
1201     }
1202     if(!isset($SESSION->cal_show_user)) {
1203         $SESSION->cal_show_user = true;
1204     }
1205    // if(empty($SESSION->cal_courses_shown)) {
1206         $SESSION->cal_courses_shown = calendar_get_default_courses(true);
1207     //}
1208     if(empty($SESSION->cal_users_shown)) {
1209         // The empty() instead of !isset() here makes a whole world of difference,
1210         // as it will automatically change to the user's id when the user first logs
1211         // in. With !isset(), it would never do that.
1212         $SESSION->cal_users_shown = !empty($USER->id) ? $USER->id : false;
1213     }
1214     else if(is_numeric($SESSION->cal_users_shown) && !empty($USER->id) && $SESSION->cal_users_shown != $USER->id) {
1215         // Follow the white rabbit, for example if a teacher logs in as a student
1216         $SESSION->cal_users_shown = $USER->id;
1217     }
1218 }
1219
1220 function calendar_overlib_html() {
1221     return '<div id="overDiv" style="position: absolute; visibility: hidden; z-index:1000;"></div>'
1222           .'<script type="text/javascript" src="'.CALENDAR_URL.'overlib.cfg.php"></script>';
1223 }
1224
1225 function calendar_set_referring_course($courseid) {
1226     global $SESSION;
1227     $SESSION->cal_course_referer = intval($courseid);
1228 }
1229
1230 function calendar_set_filters(&$courses, &$group, &$user, $courseeventsfrom = NULL, $groupeventsfrom = NULL, $ignorefilters = false) {
1231     global $SESSION, $USER, $CFG;
1232
1233     // Insidious bug-wannabe: setting $SESSION->cal_courses_shown to $course->id would cause
1234     // the code to function incorrectly UNLESS we convert it to an integer. One case where
1235     // PHP's loose type system works against us.
1236     if(is_string($SESSION->cal_courses_shown)) {
1237         $SESSION->cal_courses_shown = intval($SESSION->cal_courses_shown);
1238     }
1239
1240     if($courseeventsfrom === NULL) {
1241         $courseeventsfrom = $SESSION->cal_courses_shown;
1242     }
1243     if($groupeventsfrom === NULL) {
1244         $groupeventsfrom = $SESSION->cal_courses_shown;
1245     }
1246
1247     if(($SESSION->cal_show_course && $SESSION->cal_show_global) || $ignorefilters) {
1248         if(is_int($courseeventsfrom)) {
1249             $courses = array(SITEID, $courseeventsfrom);
1250         }
1251         else if(is_array($courseeventsfrom)) {
1252             $courses = array_keys($courseeventsfrom);
1253             $courses[] = SITEID;
1254         }
1255     }
1256     else if($SESSION->cal_show_course) {
1257         if(is_int($courseeventsfrom)) {
1258             $courses = array($courseeventsfrom);
1259         }
1260         else if(is_array($courseeventsfrom)) {
1261             $courses = array_keys($courseeventsfrom);
1262         }
1263         $courses = array_diff($courses, array(SITEID));
1264     }
1265     else if($SESSION->cal_show_global) {
1266         $courses = array(SITEID);
1267     }
1268     else {
1269         $courses = false;
1270     }
1271     //BUG 6130 clean $courses array as SESSION has bad entries.
1272     // [pj] TODO: See if this has to do with my new change in get_default_courses and can be taken out
1273     if (is_array($courses)) {
1274         foreach ($courses as $index => $value) {
1275             if (empty($value)) unset($courses[$index]);
1276         }
1277
1278         // Sort courses for consistent colour highlighting
1279         // Effectively ignoring SITEID as setting as last course id
1280         $key = array_search(SITEID, $courses);
1281         if ($key !== false) {
1282             unset($courses[$key]);
1283             sort($courses);
1284             $courses[] = SITEID;
1285         } else {
1286             sort($courses);
1287         }
1288     }
1289
1290     if($SESSION->cal_show_user || $ignorefilters) {
1291         // This doesn't work for arrays yet (maybe someday it will)
1292         $user = $SESSION->cal_users_shown;
1293     }
1294     else {
1295         $user = false;
1296     }
1297     if($SESSION->cal_show_groups || $ignorefilters) {
1298         if(is_int($groupeventsfrom)) {
1299             $groupcourses = array($groupeventsfrom);
1300         }
1301         else if(is_array($groupeventsfrom)) {
1302             $groupcourses = array_keys($groupeventsfrom);
1303         }
1304
1305         // XXX TODO: not sure how to replace $CFG->calendar_adminseesall
1306         if(has_capability('moodle/calendar:manageentries', get_context_instance(CONTEXT_SYSTEM, SITEID)) && !empty($CFG->calendar_adminseesall)) {
1307             $group = true;
1308         }
1309         else {
1310             $grouparray = array();
1311
1312             // We already have the courses to examine in $courses
1313             // For each course...
1314
1315             foreach($groupcourses as $courseid) {
1316
1317                 // If the user is an editing teacher in there,
1318                 if(!empty($USER->id) && has_capability('moodle/calendar:manageentries', get_context_instance(CONTEXT_COURSE, $courseid))) {
1319                     // If this course has groups, show events from all of them
1320                     if(is_int($groupeventsfrom)) {
1321                         $courserecord = get_record('course', 'id', $courseid);
1322                         if ($courserecord->groupmode != NOGROUPS || !$courserecord->groupmodeforce) {
1323                             $groupids[] = $courseid;
1324                         }
1325                     }
1326                     else if(isset($SESSION->cal_courses_shown[$courseid]) && ($SESSION->cal_courses_shown[$courseid]->groupmode != NOGROUPS || !$SESSION->cal_courses_shown[$courseid]->groupmodeforce)) {
1327                         $groupids[] = $courseid;
1328                     }
1329                 }
1330
1331                 // Otherwise (not editing teacher) show events from the group he is a member of
1332                 else if(isset($USER->groupmember[$courseid])) {
1333                     //changed to 2D array
1334                     foreach ($USER->groupmember[$courseid] as $groupid){
1335                         $grouparray[] = $groupid;
1336                     }
1337                 }
1338             }
1339
1340             if (!empty($groupids)) {
1341                 $sql = "SELECT id
1342                         FROM {$CFG->prefix}groups
1343                         WHERE courseid IN (".implode(',', $groupids).')';
1344
1345                 if ($grouprecords= get_records_sql($sql)) {
1346                     $grouparray = array_merge($grouparray, array_keys($grouprecords));
1347                 }
1348             }
1349
1350             if(empty($grouparray)) {
1351                 $group = false;
1352             }
1353             else {
1354                 $group = $grouparray;
1355             }
1356         }
1357
1358     }
1359     else {
1360         $group = false;
1361     }
1362 }
1363
1364 function calendar_edit_event_allowed($event) {
1365
1366     global $USER;
1367
1368     // can not be using guest account
1369     if ($USER->username == "guest") {
1370         return false;
1371     }
1372
1373     $sitecontext = get_context_instance(CONTEXT_SYSTEM, SITEID);
1374     // if user has manageentries at site level, return true
1375     if (has_capability('moodle/calendar:manageentries', $sitecontext)) {
1376         return true;
1377     }
1378
1379     // if groupid is set, it's definitely a group event
1380     if ($event->groupid) {
1381         //TODO:check.
1382         if (! groups_group_exists($event->groupid)) {
1383             return false;
1384         }
1385
1386         // this is ok because if you have this capability at course level, you should be able
1387         // to edit group calendar too
1388         // there is no need to check membership, because if you have this capability
1389         // you will have a role in this group context
1390         return has_capability('moodle/calendar:manageentries', get_context_instance(CONTEXT_GROUP, $event->groupid));
1391     } else if ($event->courseid) {
1392     // if groupid is not set, but course is set,
1393     // it's definiely a course event
1394         return has_capability('moodle/calendar:manageentries', get_context_instance(CONTEXT_COURSE, $event->courseid));
1395     } else if ($event->userid && $event->userid == $USER->id) {
1396     // if course is not set, but userid id set, it's a user event
1397         return (has_capability('moodle/calendar:manageownentries', $sitecontext));
1398     }
1399     return false;
1400 }
1401
1402 function calendar_get_default_courses($ignoreref = false) {
1403     global $USER, $CFG, $SESSION;
1404
1405     if(!empty($SESSION->cal_course_referer) && !$ignoreref) {
1406         return array($SESSION->cal_course_referer => 1);
1407     }
1408
1409     if(empty($USER->id)) {
1410         return array();
1411     }
1412
1413     $courses = array();
1414     if (has_capability('moodle/calendar:manageentries', get_context_instance(CONTEXT_SYSTEM, SITEID))) {
1415         if (!empty($CFG->calendar_adminseesall)) {
1416             $courses = get_records_sql('SELECT id, 1 FROM '.$CFG->prefix.'course');
1417             return $courses;
1418         }
1419     }
1420
1421     if (isset($CFG->adminseesall)) {
1422         $courses = get_my_courses($USER->id, null, null, $CFG->adminseesall);
1423     }
1424     else {
1425         $courses = get_my_courses($USER->id, null, null, false);
1426     }
1427
1428     return $courses;
1429 }
1430
1431 function calendar_preferences_button() {
1432     global $CFG, $USER;
1433
1434     // Guests have no preferences
1435     if (empty($USER->id) || isguest()) {
1436         return '';
1437     }
1438
1439     return "<form $CFG->frametarget method=\"get\" ".
1440            " action=\"$CFG->wwwroot/calendar/preferences.php\">".
1441            "<div><input type=\"submit\" value=\"".get_string("preferences", "calendar")." ...\" /></div></form>";
1442 }
1443
1444 function calendar_format_event_time($event, $now, $morehref, $usecommonwords = true, $showtime=0) {
1445     $startdate = usergetdate($event->timestart);
1446     $enddate = usergetdate($event->timestart + $event->timeduration);
1447     $usermidnightstart = usergetmidnight($event->timestart);
1448
1449     if($event->timeduration) {
1450         // To avoid doing the math if one IF is enough :)
1451         $usermidnightend = usergetmidnight($event->timestart + $event->timeduration);
1452     }
1453     else {
1454         $usermidnightend = $usermidnightstart;
1455     }
1456
1457     // OK, now to get a meaningful display...
1458     // First of all we have to construct a human-readable date/time representation
1459
1460     if($event->timeduration) {
1461         // It has a duration
1462         if($usermidnightstart == $usermidnightend ||
1463            ($event->timestart == $usermidnightstart) && ($event->timeduration == 86400 || $event->timeduration == 86399) ||
1464            ($event->timestart + $event->timeduration <= $usermidnightstart + 86400)) {
1465             // But it's all on the same day
1466             $timestart = calendar_time_representation($event->timestart);
1467             $timeend = calendar_time_representation($event->timestart + $event->timeduration);
1468             $time = $timestart.' <strong>&raquo;</strong> '.$timeend;
1469
1470             if ($event->timestart == $usermidnightstart && ($event->timeduration == 86400 || $event->timeduration == 86399)) {
1471                 $time = get_string('allday', 'calendar');
1472             }
1473
1474             // Set printable representation
1475             if (!$showtime) {
1476                 $day = calendar_day_representation($event->timestart, $now, $usecommonwords);
1477                 $eventtime = calendar_get_link_tag($day, CALENDAR_URL.'view.php?view=day'.$morehref.'&amp;', $enddate['mday'], $enddate['mon'], $enddate['year']).', '.$time;
1478             } else {
1479                 $eventtime = $time;
1480             }
1481         } else {
1482             // It spans two or more days
1483             $daystart = calendar_day_representation($event->timestart, $now, $usecommonwords).', ';
1484             if ($showtime == $usermidnightstart) {
1485                 $daystart = '';
1486             }
1487             $timestart = calendar_time_representation($event->timestart);
1488             $dayend = calendar_day_representation($event->timestart + $event->timeduration, $now, $usecommonwords).', ';
1489             if ($showtime == $usermidnightend) {
1490                 $dayend = '';
1491             }
1492             $timeend = calendar_time_representation($event->timestart + $event->timeduration);
1493
1494             // Set printable representation
1495             if ($now >= $usermidnightstart && $now < ($usermidnightstart + 86400)) {
1496                 $eventtime = $timestart.' <strong>&raquo;</strong> '.calendar_get_link_tag($dayend, CALENDAR_URL.'view.php?view=day'.$morehref.'&amp;', $enddate['mday'], $enddate['mon'], $enddate['year']).
1497                 $timeend;
1498             } else {
1499                 $eventtime = calendar_get_link_tag($daystart, CALENDAR_URL.'view.php?view=day'.$morehref.'&amp;', $startdate['mday'], $startdate['mon'], $startdate['year']).
1500                 $timestart.' <strong>&raquo;</strong> '.calendar_get_link_tag($dayend, CALENDAR_URL.'view.php?view=day'.$morehref.'&amp;', $enddate['mday'], $enddate['mon'], $enddate['year']).
1501                 $timeend;
1502             }
1503         }
1504     } else {
1505         $time = ' ';
1506
1507         // Set printable representation
1508         if (!$showtime) {
1509             $day = calendar_day_representation($event->timestart, $now, $usecommonwords);
1510             $eventtime = calendar_get_link_tag($day, CALENDAR_URL.'view.php?view=day'.$morehref.'&amp;', $startdate['mday'], $startdate['mon'], $startdate['year']).trim($time);
1511         } else {
1512             $eventtime = $time;
1513         }
1514     }
1515
1516     if($event->timestart + $event->timeduration < $now) {
1517         // It has expired
1518         $eventtime = '<span class="dimmed_text">'.str_replace(' href=', ' class="dimmed" href=', $eventtime).'</span>';
1519     }
1520
1521     return $eventtime;
1522 }
1523
1524 function calendar_print_month_selector($name, $selected) {
1525
1526     $months = array();
1527
1528     for ($i=1; $i<=12; $i++) {
1529         $months[$i] = userdate(gmmktime(12, 0, 0, $i, 15, 2000), '%B');
1530     }
1531
1532     choose_from_menu($months, $name, $selected, '');
1533 }
1534
1535 function calendar_get_filters_status() {
1536     global $SESSION;
1537
1538     $status = 0;
1539     if($SESSION->cal_show_global) {
1540         $status += 1;
1541     }
1542     if($SESSION->cal_show_course) {
1543         $status += 2;
1544     }
1545     if($SESSION->cal_show_groups) {
1546         $status += 4;
1547     }
1548     if($SESSION->cal_show_user) {
1549         $status += 8;
1550     }
1551     return $status;
1552 }
1553
1554 function calendar_set_filters_status($packed_bitfield) {
1555     global $SESSION, $USER;
1556
1557     if(!isset($USER) || empty($USER->id)) {
1558         return false;
1559     }
1560
1561     $SESSION->cal_show_global = ($packed_bitfield & 1);
1562     $SESSION->cal_show_course = ($packed_bitfield & 2);
1563     $SESSION->cal_show_groups = ($packed_bitfield & 4);
1564     $SESSION->cal_show_user   = ($packed_bitfield & 8);
1565
1566     return true;
1567 }
1568
1569 function calendar_get_allowed_types(&$allowed) {
1570     global $USER, $CFG, $SESSION;
1571     $sitecontext = get_context_instance(CONTEXT_SYSTEM);
1572     $allowed->user = has_capability('moodle/calendar:manageownentries', $sitecontext);
1573     $allowed->groups = false; // This may change just below
1574     $allowed->courses = false; // This may change just below
1575     $allowed->site = has_capability('moodle/calendar:manageentries', get_context_instance(CONTEXT_COURSE, SITEID));
1576
1577     if(!empty($SESSION->cal_course_referer) && $SESSION->cal_course_referer != SITEID && has_capability('moodle/calendar:manageentries', get_context_instance(CONTEXT_COURSE, $SESSION->cal_course_referer))) {
1578         $course = get_record('course', 'id', $SESSION->cal_course_referer);
1579
1580         $allowed->courses = array($course->id => 1);
1581
1582         if($course->groupmode != NOGROUPS || !$course->groupmodeforce) {
1583             $allowed->groups = (boolean)groups_get_all_groups($SESSION->cal_course_referer);
1584         }
1585     }
1586 }
1587
1588 /**
1589  * see if user can add calendar entries at all
1590  * used to print the "New Event" button
1591  * @return bool
1592  */
1593 function calendar_user_can_add_event() {
1594     calendar_get_allowed_types($allowed);
1595     return (bool)($allowed->user || $allowed->groups || $allowed->courses || $allowed->site);
1596 }
1597 ?>